Did he say why?
Cant remember where I heard/read that and he probably not used the word cosmic but just that it felt the best. I kinda agree when listening to his later year mixes. Alot of Belgian new beat is around 105 too.
123
First and second ep were exclusively 123 and it was actually the title of my first ep. 
Reason: Feels good.
I’ve been varying tempos a bit more lately though, but 123 is still my fav for 4 to the floor stuff.